System and method for pruning an over-defined system model

Patent metadata

Field	Value
Publication number	US-9245072-B2
Application number	US-201213732173-A
Country	US
Kind code	B2
Filing date	Dec 31, 2012
Priority date	Dec 31, 2012
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

Methods and apparatuses are provided to select coefficients for modeling a system. Data collected from the system is used to generate a data matrix. An upper triangular matrix can be generated in accordance with the data matrix, and the upper triangular matrix can be pruned to remove selected rows and columns from the upper triangular matrix, thereby generating a pruned data matrix. A coefficient vector can be generated in accordance with the pruned data matrix. Various alternative methods of selecting coefficients for modeling the system, as well as apparatus, devices, and systems for performing said methods, are also provided.

First claim

What is claimed is:

1. A method of selecting coefficients for modeling a system, the method comprising:
receiving data collected from a power amplifier, the power amplifier exhibiting a non-linear gain characteristic, wherein a distortion circuit introduces an inverse distortion signal into an input of the power amplifier;
forming a data matrix comprising the data collected from the power amplifier;
generating an upper triangular matrix in accordance with the data matrix, the upper triangular matrix comprising a plurality of diagonal elements;
pruning the upper triangular matrix to remove one or more columns of the upper triangular matrix comprising diagonal elements that are smaller than a threshold diagonal element, thereby generating a pruned data matrix;
generating a coefficient vector in accordance with the pruned data matrix;
generating an inverse distortion signal from the coefficient vector; and
introducing the inverse distortion signal into the input of the power amplifier.

2. The method of claim 1 , wherein generating the upper triangular matrix in accordance with the data matrix includes performing a QR-Recursive-Least-Squares (QR-RLS) operation on the data collected from the system to obtain the upper triangular matrix.

3. The method of claim 1 , wherein the threshold diagonal element is determined in accordance with the following formula:

[

∑

i
=

L
+
1

N

⁢



r
ii

~



2

∑

i
=
1

N

⁢



r
ii

~



2

]

<

p
th

,

where is a given diagonal element of the upper triangular matrix having an N-by-N dimension, and where p th is a pruning threshold.

4. An apparatus comprising:
a processor; and
a computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
receive data collected from a power amplifier, the power amplifier exhibiting a non-linear gain characteristic, wherein a distortion circuit introduces an inverse distortion signal into an input of the power amplifier;
form a data matrix comprising the data collected from a system, the upper triangular matrix comprising a plurality of diagonal elements;
generate an upper triangular matrix in accordance with the data matrix;
prune the upper triangular matrix to remove one or more columns of the upper triangular matrix comprising diagonal elements that are smaller than a threshold diagonal element, thereby generating a pruned data matrix;

generate a coefficient vector in accordance with the pruned data matrix;
generate an inverse distortion signal from the coefficient vector; and
introduce the inverse distortion signal into the input of the power amplifier.

5. The apparatus of claim 4 , wherein the instructions to generate the upper triangular matrix in accordance with the data matrix include instructions to perform a QR-Recursive-Least-Squares (QR-RLS) operation on the data matrix to obtain the upper triangular matrix.

6. The apparatus of claim 4 , wherein the instructions to prune the upper triangular matrix include instructions to determine the threshold diagonal element in accordance with the following formula:

[

∑

i
=

L
+
1

N

⁢



r
ii

~



2

∑

i
=
1

N

⁢



r
ii

~



2

]

<

p
th

,

where is a given diagonal element of the upper triangular matrix having an N-by-N dimension, and where p th is a pruning threshold.

7. A method of selecting coefficients for modeling a system, the method comprising:
collecting data from a power amplifier to form a data matrix, the power amplifier exhibiting a non-linear gain characteristic, wherein a distortion circuit introduces an inverse distortion signal into an input of the power amplifier;
performing column sorting on the data matrix to produce a permutated data matrix;
performing QR decomposition on the permutated data matrix to produce an upper triangular matrix, the upper triangular matrix comprising a plurality of diagonal elements;
pruning the upper triangular matrix to remove one or more columns of the upper triangular matrix that are highly correlated with remaining leftmost columns of the upper triangular matrix, thereby generating a pruned data matrix;

Assignees

• Huawei Tech Co Ltd

Inventors

• Jia Ming
• Nikopour Hosein

Classifications

• G06F30/367 Primary

  Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods · CPC title

• G06F17/5036 Primary

  Physics · mapped topic